Cutter with laser generator that irradiates cutting position on workpiece to facilitate alignment of blade with cutting position

ABSTRACT

A cutter including a base, a holder, a cutter blade portion, and a laser generator. The holder is supported on the base portion in an upright posture. The cutter blade portion supports a moving blade. The cutter blade portion is supported on the holder movable between an upper position and a lower position. The cutter blade portion is moved into the lower position to cut a workpiece supported on the base using the moving blade. The laser generator is attached to the holder or the cutter blade portion in an orientation to direct at least a portion of the laser light onto a position on the workpiece that is directly beneath the cutter blade portion when the cutter blade portion is in the upper position. Alternatively, a holder has a shaft support portion, and a slide shaft is axially slidably supported by the shaft support portion. A front end of the slide shaft has a hinge holder which pivotally supports the cutting blade portion. A laser generator is fixed to a front side of the hinge holder.

CROSS REFERENCE TO RELATED APPLICATION

This application is a continuation application of copending U.S. patentapplication Ser. No. 11/509,759, filed Aug. 25, 2006, which is adivisional of U.S. patent application Ser. No. 09/930,442 filed on Aug.16, 2001, which is a continuation-in-part of U.S. patent applicationSer. No. 09/499,385 filed Feb. 7, 2000, now abandoned, and furtherclaims priority based on 35 U.S.C. section 119 to Japanese PatentApplication Nos. 11-28275 filed Feb. 5, 1999, 11-28277 filed Feb. 5,1999, 11-335411 filed Nov. 26, 1999, and 11-344301 filed Dec. 3, 1999.The entire disclosures of the prior applications Ser. Nos. 11,509,759,09/930,442 and 09/499,385 are hereby incorporated by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a cutter, such as a tabletop circularsaw for cutting wooden boards.

2. Description of the Related Art

There has been known a cutter with a circular blade and a lasergenerator. The laser generator irradiates the workpiece with a laserlight to indicate the position where the cutting is to be performed. Theoperator then uses the circular blade to cut the workpiece material atthe position indicated by the laser light.

Japanese Utility-Model-Application Publication No. SHO-62-150019discloses a cutter with a blade positioned above a workpiece and a lasergenerator fixed on the blade support at a position above the blade.Before cutting the workpiece, the user draws a mark on the workpiece toindicate the position on the workpiece to be cut. The user then alignsthe laser light emitted from the laser generator with the mark on theworkpiece, and lowers the blade to cut the workpiece.

The laser generator disclosed in Japanese Utility-Model-ApplicationPublication No. SHO-62-150019 is fixed at the blade support. Therefore,if the laser light is not actually in alignment with the location thatthe blade cuts, the user must attempt to compensate for this positionaldifference by intentionally shifting the laser light out of alignmentwith the cutting position mark on the workpiece before cutting theworkpiece. This increases the possibility that the workpiece will not becut in the desired cutting position.

West German Patent Publication No. 3406904 discloses a cutter providedwith a laser generator mounted on a slide bar. The laser generator canbe freely slid horizontally along the slide bar to adjust position wherethe laser light irradiates the workpiece. However, minute adjustment ofwhere the laser light irradiates the workpiece is difficult with thisconfiguration.

U.S. Pat. Nos. 5,285,708 and 5,375,495 disclose cutters, each having acutting portion that is disposed above the workpiece, and a lasergenerator that is disposed above and ahead of the cutting blade. A railis suspended above the cutting blade so as to extend in a widthwisedirection of the cutting blade. A groove is formed in the lasergenerator to fit in the rail. The laser generator is guided by along therail so can easily moved in the horizontal direction. However, if thegroove in the laser generator and the rail have a poor fit with gapstherebetween, then horizontal movement of the laser generator will beunstable so that the cutting position cannot be accurately indicatedusing the laser.

Next, a conventional mechanism for adjusting alignment of a laser lightwith a vertical reference line Y and with a horizontal reference line Xwill be explained with reference to FIGS. 1 (a) to 3. A cylindricallaser generator 70 is supported in a support member 71 by a fixing screw72. The fixing screw 72 presses the laser generator 70 downward in thesupport member 71. The support member 71 is fixed to a base by two bolts74, 74. One bolt 74 passes through a circular hole 76 and the other bolt74 passes an elongated hole 77.

As shown in FIGS. 1 (a) and 1 (b), when laser light L1 from thecylindrical laser generator 70 is to be aligned with a verticalreference line Y, the fixing screw 72 is loosened and the cylindricallaser generator 70 is rotated within the support member 71 until thelaser light L1 is aligned with the vertical reference line Y. Oncealignment is achieved, the fixing screw 72 is retightened to fix thecylindrical laser generator 70 in place in the support member 71.

As shown in FIG. 2, when the laser light L1 is to be aligned with ahorizontal reference line X, the bolts 74, 74 are loosened and thesupport member 71 is pivoted around the circular hole 76 within thehorizontal plane. When the laser light L1 is aligned with the horizontalreference line X, then the bolts 74, 74 are tightened to fix the supportmember 71 in place.

However, because the tip of the fixing screw 72 is not completely flat,the cylindrical laser generator 70 might be moved out of alignment whenthe fixing screw 72 is tightened. When this happens, the operator mustrepeat the adjustment process until the laser light L1 is accuratelyaligned with the vertical reference line Y.

Also, when the bolt 74 is tightened, the support member 71 might movebecause the contacting surface of the support member 71 or the bolts 74are slanted. In this case also, the operator must repeat the adjustmentprocess until the laser light L1 is accurately aligned with thehorizontal reference line X.

SUMMARY OF THE INVENTION

As shown in FIGS. 4 and 5, normally laser light L1 has a different widthW1 than the width W2 cut by the blade. For example, a circular blade 22with an outer diameter of 255 mm will cut the workpiece to a width W2 ofgenerally 2.5 mm. In contrast, laser light L1 normally has a width W1 ofabout 0.8 mm. For this reason, an operator could conceivably align thelaser light L1 with the cutting position on the workpiece in any of theways shown in FIGS. 4 to 7 (b). For example, the operator couldconceivably align the laser light L1 with the exterior of the left edgeof the cutting width as shown in FIGS. 5 and 7 (a), or with the exteriorof the right edge of the cutting width as shown in FIG. 7 (b).

Alternatively, the operator could conceivably align the laser light L1with the interior of the left edge of the blade width W2 as shown inFIGS. 4 and 6 (a), or with the interior of the right edge of the bladewidth W2 as shown in FIG. 6 (b). However, it is impossible to align thelaser light L1 with the interior of the left or right edges of the bladewidth W2 using the configuration disclosed in U.S. Pat. Nos. 5,285,708and 5,375,495, because the cutting blade is interposed between the lasergenerator and the workpiece. If a user attempts to irradiate theworkpiece in the manner indicated either in FIGS. 6 (a) or 6 (b), thatis, with the laser light L1 irradiating the interior of either the leftor right edge of the cutting width W2, then the laser light L1 will hitthe upper edge of the cutting blade itself, rather than the workpiece.In other words, the cutting blade will block the laser light L1 andprevent the laser light from indicating the cutting position on theworkpiece. As a result, the user is only capable of irradiating theworkpiece with the laser light in alignment with the exterior of theright or left edge of the cutting width W2.

West German Patent No. DE 29616604 discloses a cutter with a lasergenerator disposed far from the blade portion. With this configuration,a long extension member must be provided to connect the laser generatorwith the blade holding member, so that the laser generator is disposedfar enough from the blade holding member. This extension member makesgets in the way during cutting operations, and contributes toundesirable overall enlargement of the cutter.

It is an object of the present invention to overcome the above-describedproblems and to provide a cutter with a laser generator capable ofirradiating a desired position on the workpiece with laser light,without interference from the cutter blade.

It is another objective of the present invention to provide a cutterwith a laser generator capable of adjusting alignment of emitted laserlight in both the horizontal and vertical directions.

It is still another objective of the present invention to provide acutter with a laser generator wherein width of laser light emitted bythe laser generator can be adjusted.

In order to achieve the above-described objectives, a cutter accordingto one aspect of the present invention includes a base for supporting aworkpiece, a holder supported on the base portion in an upright posture,a cutter blade portion, and a laser generator for emitting laser light.The cutter blade portion is adapted for supporting a moving blade thatcuts the workpiece. The cutter blade portion is supported on the holdermovable between an upper position and a lower position, wherein thecutter blade portion is closer to the base in the lower position than inthe upper position.

The laser generator is attached to one of the holder and the cutterblade portion in an orientation to direct at least a portion of thelaser light onto a position on the workpiece that is directly beneaththe cutter blade portion with respect to the cutter blade portion in theupper position. With this configuration, a desired position to cut theworkpiece can be indicated even if the position is directly beneath thecutting blade.

A cutter according to another aspect of the present invention includes abase, a cutter blade portion, a laser generator, a laser generatorsupport member, and means for moving the light emitting portion of thelaser generator in a horizontal direction. The laser generator supportmember supports therein the laser generator slidable in the horizontaldirection. The moving means is adapted for moving the light emittingportion of the laser generator in the horizontal direction. With thisconfiguration, the position of the light emitting portion can be easilyadjusted in the horizontal direction using a simple moving means such asa screw.

A cutter according to still another aspect of the present inventionincludes a base, a cutter blade portion, a laser generator, a lasergenerator support member, a pivot means, first and second regulationmembers screwingly fitted in the laser generator support member, andfirst and second resilient means. The pivot means enables the lasergenerator to pivot horizontally and vertically in the laser generatorsupport member. The first regulation member presses against the lasergenerator to pivot the laser generator horizontally about the pivotmeans, and the second regulation member presses against the lasergenerator to pivot the laser generator vertically about the pivot means.The first and second resilient means urge the laser generator toward thefirst and second regulation members, respectively. This configurationenables easy adjustment of the laser generator in both vertical andhorizontal directions, while eliminating any looseness of fit betweenthe laser generator and the laser generator support member.

A cutter according to a further aspect of the present invention includesa base portion, a cutter blade portion, a laser generator, a convex lensprovided in the laser generator, and a lens moving unit. The convex lensis for adjusting the focal point of the laser light emitted by the lasergenerator. The lens moving unit is for moving the convex lens parallelwith optical axis of the laser light emitted from the laser generator tochange the width of the laser light. With this configuration, the widthof the laser light can be adjusted by merely using the lens moving unitto move the position of the convex lens.

A cutter according to still a further aspect of the present inventionincludes a base portion, a cutter blade portion, a laser generator, anda movement member. The laser generator has a light emitting portion fromwhich the laser light is emitted, and a stationary wall positioned infront of the light emitting portion. A movable member is disposed inconfrontation with the stationary wall and is movable toward and awayfrom the stationary wall for changing a width of the laser light.

A cutter according to still another aspect of the present inventionincludes a base portion, a holder, a cutter blade portion provided on anupper portion of the holder, a laser generator provided on the holder,and a cleaning mechanism. The cutter blade portion is adapted for freevertical movement toward and away from the base portion between anuppermost position to a lowermost position. The cleaning mechanismcontacts a light emitting portion of the laser generator in linkingassociation with vertical movement of the cutter blade portion from theuppermost position to the lowermost position. The cleaning mechanismcleans off the light emitting portion by said contact. With thisconfiguration, the light emitting portion of the laser generator will beautomatically cleaned each time the cutter is used to cut a workpiece.

A cutter according to still another aspect of the present inventionincludes the base, a holder, at least one slide shaft, a hinge holder, acutter blade portion, and a laser generator. The holder is supported onthe base portion in an upright posture, and has a slide shaft supportportion. The at least one slide shaft extends through the slide shaftsupport portion and is slidably movable in a frontward and a rearwarddirection with respect to the slide shaft support portion. The hingeholder fixed to a front end of the at least one slide shaft. The cutterblade portion is adapted for supporting a moving blade that cuts theworkpiece. The cutter blade portion is supported on the hinge holder soas to be movable between an upper position and a lower position. Thecutter blade portion is closer to the base in the lower position than inthe upper position. The laser generator is adapted for emitting laserlight. The laser generator is attached to a front side of the hingeholder in an orientation to direct at least a portion of the laser lightonto a position on the workpiece that is directly beneath the cutterblade portion with respect to the cutter blade portion in the upperposition.

BRIEF DESCRIPTION OF THE DRAWINGS

The particular features and advantages of the invention as well as otherobjects will become more apparent from the following description takenin connection with the accompanying drawings, in which:

FIG. 1 (a) is a side view showing a conventional laser unit;

FIG. 1 (b) is a schematic view indicating a laser light out of alignmentfrom a vertical reference line;

FIG. 2 is a top view of the conventional laser unit shown in FIG. 1( a),with laser light emitted from the laser unit out of alignment with ahorizontal reference line;

FIG. 3 is a side view of the conventional laser unit shown in FIG. 1(a);

FIG. 4 is perspective view showing a workpiece irradiated in aconceivable manner by a laser light along an inner edge of a width to becut;

FIG. 5 is perspective view showing a workpiece irradiated in aconceivable manner by a laser light along an outer edge of a width to becut;

FIG. 6 (a) is a schematic view showing a workpiece irradiated in aconceivable manner by a laser light along an inner left edge of a widthto be cut;

FIG. 6 (b) is a schematic view showing a workpiece irradiated in aconceivable manner by a laser light along an inner right edge of a widthto be cut;

FIG. 7 (a) is a schematic view showing a workpiece irradiated in aconceivable manner by a laser light along an outer left edge of a widthto be cut;

FIG. 7 (b) is a schematic view showing a workpiece irradiated in aconceivable manner by a laser light along an outer right edge of a widthto be cut;

FIG. 8 is a side view showing a cutter according to a first embodimentof the present invention;

FIG. 9 is a partial view showing the cutter from the rear;

FIG. 10 is a cross-sectional view taken along line X-X of FIG. 8;

FIG. 11 is a partial view showing the cutter from the front;

FIG. 12 is a cross-sectional view showing a laser unit according to thefirst embodiment, taken along line XII-XII of FIG. 11;

FIG. 13 is a cross-sectional view taken along line XIII-XIII of FIG. 12;

FIG. 14 is a cross-sectional view taken along line XIV-XIV of FIG. 13;

FIG. 15 is a side view showing a modification to the cutter of the firstembodiment, the modification including a cleaning mechanism;

FIG. 16 is an enlarged view showing the cleaning mechanism of FIG. 15;

FIG. 17 is an enlarged view showing a brush of the cleaning mechanismmoving into contact with a light emitting portion of the lasergenerator;

FIG. 18 is an enlarged view showing the brush cleaning sawdust off thelight emitting portion;

FIG. 19 is a cross-sectional view showing a laser unit according to asecond embodiment of the present invention;

FIG. 20 is a cross-sectional view taken along line XX-XX of FIG. 19;

FIG. 21 is a cross-sectional view showing a laser unit according to athird embodiment of the present invention;

FIG. 22 is a cross-sectional view showing a laser unit according to afourth embodiment of the present invention;

FIG. 23 is a cross-sectional view showing a laser unit according to afifth embodiment of the present invention;

FIG. 24 is a cross-sectional view showing a laser unit according to asixth embodiment of the present invention;

FIG. 25 is a cross-sectional view showing a laser unit according to aseventh embodiment of the present invention;

FIG. 26 is a cross-sectional view taken along line XXVI-XXVI of FIG. 25;

FIG. 27 is a cross-sectional view taken along line XXVII-XXVII of FIG.26;

FIG. 28 (a) is a schematic view showing laser generators according toseventh, eighth, and ninth embodiments of the present invention emittinglaser light;

FIG. 28 (b) is a schematic view showing laser light from the lasergenerators of FIG. 28 (a) out of alignment from a vertical referenceline;

FIG. 29 is a schematic view showing a workpiece with the location to becut indicated by a drawn line;

FIG. 30 is a cross-sectional view showing a laser unit according to aneighth embodiment of the present invention;

FIG. 31 is a cross-sectional view taken along line XXXI-XXXI of FIG. 30;

FIG. 32 is a cross-sectional view taken along line XXXII-XXXII of FIG.31;

FIG. 33 is a cross-sectional view showing a laser unit according to aninth embodiment of the present invention;

FIG. 34 is a cross-sectional view taken along line XXXIV-XXXIV of FIG.33;

FIG. 35 is a cross-sectional view taken along line XXXV-XXXV of FIG. 34;

FIG. 36 is a perspective view showing a laser unit according to a tenthembodiment of the present invention;

FIG. 37 is a cross-sectional view taken along line XXXVII-XXXVII of FIG.36;

FIG. 38 is a cross-sectional view taken along line XXXVIII-XXXVIII ofFIG. 36;

FIG. 39 is a perspective view showing cutting of a workpiece;

FIG. 40 is a perspective view showing a laser unit according to aneleventh embodiment of the present invention with laser light emittedtherefrom adjusted to a minimum width;

FIG. 41 is a perspective view showing the laser unit of FIG. 40 withlaser light emitted adjusted to a maximum width;

FIG. 42 is a side view showing a cutter according to a twelfthembodiment of the present invention;

FIG. 43 is a side view showing a cutter according to a thirteenthembodiment of the present invention;

FIG. 44 is a front view showing the cutter according to the thirteenthembodiment;

FIG. 45 is a cross-sectional view taken in the direction of an arrowXXXXV of FIG. 46 for showing a shaft support portion of a holder in thecutter according to the thirteenth embodiment; and, FIG. 46 is partialside view showing a cutting state of the cutter according to thethirteenth embodiment.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Cutters according to first through thirteenth embodiments of the presentinvention will be explained while referring to the accompanyingdrawings. Unless otherwise noted, orientation terms, such as left,right, front, rear, up, and down, are used with respect to the normalorientation of the device for normal use. The cutters according to thefirst through eleventh embodiments have substantially the sameconfiguration with exception of components relating to the laser unit.As will be described in more detail later, the laser units of the firstthrough sixth embodiments are configured to enable adjustment inhorizontal position of the laser generator. The laser units of theseventh through ninth embodiments include configuration that enablesadjustment of the laser generator to align emitted light in the verticaland horizontal directions. The laser units of the tenth and eleventhembodiments are configured to enable adjustment in the width of thelaser light emitted from the laser generator. The cutters according tothe twelfth and thirteenth embodiments are the modifications to thecutters of the first through eleventh embodiment.

First, a cutter D1 according to the first embodiment will be describedwhile referring to FIGS. 8 to 14. As shown in FIG. 8, the cutter D1 hasa base 1, a turntable 2, a fence 3, a holder shaft 4, a holder 10, aclamp lever 5, a shaft 11, a cutter mechanism 20, and a laser unit U.The turntable 2 is supported on the center of the base 1 so as to befreely rotatable horizontally. The upper surface of the turntable 2shares the same plane with the upper surface of the base 1. A workpieceM, such as a wooden board, is placed on the upper surfaces of the base 1and the turntable 2. The fence 3 is fixed on the upper surface of thebase 1 to support the side surface of the workpiece M. The holder 10 issupported in an upright posture on the rear end of the turntable 2 bythe holder shaft 4. The axial center of the holder shaft 4 is alignedsubstantially with the upper surface of the turntable 2. The holder 10can be pivoted leftward or rightward with respect to the surface of theturntable 2 about the holder shaft 4.

As shown in FIG. 9, an elongated hole 10 a is formed in the rear portionof the holder 10 with a curved shape centered on the holder shaft 4. Theclamp lever 5 passes through the elongated hole 10 a. A screw portion 6formed on the tip of the clamp lever 5 is screwed into a screw holeformed in the rear surface of the turntable 2. When the screw portion 6of the clamp lever 5 is loosened, the holder 10 can be pivoted aroundthe holder shaft 4 within the range defined by the elongated hole 10 a.When the screw portion 6 is retightened, the holder 10 is squeezedbetween the turntable 2 and the clamp lever 5 and fixed in a desiredposition. It should be noted that the elongated hole 10 a is formed withan arc range enabling the holder 10 to be pivoted left and right withina 45-degree angle.

The cutter mechanism 20 is supported above the holder 10 on a shaft 11to be freely swingable up and down with respect to the upper surface ofbase 1. A spring 12 is provided between the holder 10 and the cuttermechanism 20 to urge the cutter mechanism 20 upward.

As shown in FIGS. 8 and 10 the cutter mechanism 20 includes a cuttingblade shaft 21, a cutting blade, such as a circular saw blade 22, a sawcover 23, a gear case 24, and a handle 29. The cutter mechanism alsoincludes a motor 25, a motor shaft 26, a motor housing 28, bearings 30,31, a pulley 33, and a transmission belt 27.

The saw cover 23 covers the upper half of the cutting blade 22 and isformed integrally with the gear case 24. The motor housing 28 ispositioned above the gear case 24 and covers and supports the motor 25and the motor shaft 26. The cutting blade shaft 21 is positioned belowthe gear case 24. As shown in FIG. 10, the cutting blade 22 is fixed onone end of the cutting blade shaft 21 by a bolt 32 and is rotatablysupported on the bearings 30, 31. The motor shaft 26 is rotatablysupported on a bearing 34. The pulley 35 is provided on the exposed tipof the motor shaft 26 at a position above a pulley 33. The transmissionbelt 27 spans between the pulleys 33, 35. Power from the motor 25 istransmitted to the cutting blade 22 through the motor shaft 26, thepulleys 35, 33, the transmission belt 27, and the cutting blade shaft 21to drivingly rotate the cutting blade 22.

As shown in FIGS. 8 and 11, a V-shaped protrusion portion 13 is mountedon the front surface of the holder 10. Stopper bolts 7A, 7B arescrewingly fitted in a vertically aligned orientation in the rear uppersurface of the turntable 2 at positions along the movement orbit of theprotrusion portion 13. Therefore, when the holder 10 is tilted leftwardor rightward, then the protrusion portion 13 will abut the head portionof the corresponding stopper bolt 7A, 7B once the holder 10 is tilted toa predetermined angle. In other words, the bolts 7A, 7B determine thetilting range possible of the cutter mechanism 20. According to thepresent embodiment, the stopper bolts 7A, 7B are disposed to abut theprotrusion portion 13 when the holder 10 is pivoted to the extreme leftor right (as viewed in FIG. 11) of a 45 degree range.

Although not shown in the drawings, a blade groove plate is fixed to theupper surface of the turntable 2. The blade groove plate is formed witha groove at its center into which the cutting blade 22 enters duringcutting operations for cutting a workpiece M. During operations forcutting the workpiece M, the lower edge of the cutting blade 22 dropsbelow the upper surface of the turntable 2. At this time, the cuttingblade 22 enters into the groove of the groove plate so that the cutsurface of the workpiece M can be prevented from being roughened orscuffed by the edge of the blade 22.

As shown in FIG. 8, the laser unit U includes a support member 40 and arectangular-shaped laser generator 41. The support member 40 is fixed tothe front surface of the holder 10 and houses the laser generator 41. Asshown in FIG. 12, the support member 40 and the laser generator 41define therebetween a rectangular housing space 40 a. The lasergenerator 41 includes a light emitting portion 41 a (FIG. 13) foremitting a laser light L1. According to the present embodiment, thelight emitting portion 41 a is positioned along an imaginary lineextending from the blade edge 22 a of the cutting blade 22. The lasergenerator 41 includes a switch (not shown) for starting drive of thelight emitting portion 41 a to emit the laser light L1.

The support member 40 supports the laser generator 41 in an orientationto direct at least a portion of the emitted laser light L1 directlybeneath the blade edge 22 a of the cutting blade 22, assuming that thecutter mechanism 20 is raised in its uppermost position as shown in FIG.8. This configuration overcomes the shortcomings of the configurationdescribed in U.S. Pat. No. 5,375,495, so that the laser light L1irradiates the upper surface of the workpiece M without interferencefrom the cutting blade 22. As a result, the operator can align the laserlight L1 with the interior of left and right edges of the cutting widthW2 in the manner shown in FIGS. 6 (a) and 6 (b).

A detailed explanation of the laser unit U according to the presentembodiment will be described while referring to FIGS. 12 to 14. Thelaser unit U is configured to enable horizontal movement of the lasergenerator 41, so that the position where the laser light L1 fallsincident on the workpiece M can be minutely adjusted. For example, whenthe width W2 of the cutting blade 22 is different from the width W1 ofthe laser light L1, the laser light L1 can be directed onto theworkpiece as indicated in FIGS. 4 through 7( b), that is, aligned withthe interior or exterior of left or right edges of the cutting width W2.Because the laser generator 41 can be moved horizontally, the laserlight L1 can be aligned with any position of the cutting width W2.

As shown in FIG. 12, a screw-hole portion 40 b is formed at the leftside surface of the support member 40. A screw portion 42A of a knob 42is screwingly fitted in the screw-hole portion 40 b. The tip of the knob42 abuts against the left side surface of the laser generator 41. Acompression spring 43 is disposed between the right side wall of thesupport member 40 and the right side surface of the laser generator 41.The compression spring 43 urges the laser generator 41 toward the knob42, thereby removing any looseness in the fit between the knob 42 andthe laser generator 41. As shown in FIGS. 12 and 14, a bolt 45 passesthrough the rear wall of the support member 40 and is screwingly fixedinto a female screw opened in the laser generator 41. A compressionspring 46 is disposed between the bolt 45 and the support member 40 topull the laser generator 41 rearward. Two stoppers 47 are provided, onescrewingly penetrating through each of the left and right side walls ofthe support member 40. When the laser generator 41 is moved a certaindistance either leftward or rightward, the tip of the correspondingstopper 47 abuts the wall of the laser generator 41. In this way, thestoppers 47 restrict horizontal movement of the laser generator 41within in a predetermined range.

As shown in FIG. 13, left and right compression springs 44 are supportedbetween the upper surface of the laser generator 41 and the upper wallof the support member 40, to urge the laser generator 41 downward. Aprotruding abutment surface 40 c is provided in the rear internal sideof the support member 40, that is, in the rectangular housing space 40a, in abutting confrontation with the rear surface of the lasergenerator 41.

With this configuration, when the knob 42 is rotated to screwingly moveleftward as viewed in FIG. 12, the laser generator 41 is slidhorizontally leftward by restorative force of the compression spring 43.On the other hand, when the knob 42 is rotated to screwingly moverightward, the laser generator 41 will be pressed by the knob 42 andslid horizontally rightward against the urging force of the compressionspring 43. When the knob 42 is rotated once, the laser generator 41 willmove by an amount equivalent to only the amount that the screw portionof the knob 42 moves horizontally, thereby enabling minute adjustment ofthe laser generator 41. At this time, the laser generator 41 is urgedagainst the left, lower, and rear surfaces of the light emitting portion41 a by the compression springs 43, 44, 46 and the bolt 45, therebyremoving any looseness between the support member 40 and the lasergenerator 41. This prevents the knob 42 from being unintentionallyrotated by vibration and the like during operations, so the lasergenerator 41 will not be unintentionally moved.

Next, cutting operations using the cutter D1 according to the presentembodiment will be explained. First, the user draws a line L2 on theupper surface of the workpiece M as shown in FIG. 4. For thisexplanation it will be assumed that the user wants to use the left-handportion Ma of the workpiece M after cutting the workpiece M, and wishesto retain the line L2 on the portion Ma. In this case, when the laserlight L1 is to be aligned with the interior of the left edge of thecutting width W2 as shown in FIG. 6 (a), then the left edge of the laserlight L1 is aligned with the right edge of the line L2. On the otherhand, when the laser light L1 is to be aligned exterior of the left edgeof the cutting width W2 as shown in FIG. 7( a), then as shown in FIG. 5,the operator aligns the right edge of the laser light L1 with the rightedge of the line L2. Then, the user grasps the handle 29 of the cuttermechanism 20 and swings the cutter mechanism 20 downward so that therotating blade cuts through the workpiece M.

Next, a cleaning mechanism for cleaning the laser generator 41 will beexplained while referring to FIGS. 15 to 18. As a modification to thefirst embodiment, the cleaning mechanism is provided in order to cleanthe surface of the light emitting portion 41 a of the laser generator41. That is, during the process of cutting through the workpiece M, sawdust 63 flies toward the light emitting portion 41 a of the lasergenerator 41 in the direction indicated by an arrow in FIG. 15. In somecases, the sawdust 63 will cling to the light emitting portion 41 a asshown in FIG. 16. To remove any sawdust 63 that clings to the lightemitting portion 41 a, a brush 36 is attached to the lower rear portionof the cutter mechanism 20. The brush 36 is formed from a plurality ofresilient fibers, such as nylon fibers. When the cutter mechanism 20 islowered, the brush 36 approaches the light emitting portion 41 a asshown in FIG. 16 until the brush 36 contacts the light emitting portion41 a as shown in FIG. 17. When the brush 36 presses further against thelight emitting portion 41 a, the sawdust 63 clinging to the lightemitting portion 41 a is swept away as shown in FIG. 18. In this way,the saw dust 63 can be removed from the light emitting portion 41 a sothat the cutting position can be constantly, accurately irradiated bythe laser light L1 from the light emitting portion 41 a.

Next, the second embodiment of the present invention will be describedwhile referring to FIGS. 19 and 20. The cutter according to the secondembodiment has the same configuration as the cutter of the firstembodiment, except that the laser unit U of the first embodiment isreplaced with a laser unit U2 of the second embodiment. Therefore, onlythe laser unit U2 according to the second embodiment will be describedhereinafter.

As shown in FIG. 19, a hole 140 d is formed in the left wall of asupport member 140. A knob 142 penetrates through the left wall into therectangular housing space 40 a. A screw portion 142A of the knob 142 isscrewingly fitted in a female screw portion 141 b opened in the sidesurface of the laser generator 141. A compression spring 143 is disposedon the shaft of the knob 142 at a position between the left side wall ofthe laser generator 141 and the left wall of the support member 140. Thecompression spring 143 urges the laser generator 141 rightward to removeany looseness between the laser generator 141 and the compression spring143. The laser generator 141 can be slid horizontally either rightwardor leftward by rotating the know 142. Other configuration of the laserunit U2 is as same as in the laser unit U, so further description willbe omitted. Cutting operations according to the configuration of thesecond embodiment are also the same as those described for the firstembodiment.

Next, the third embodiment will be described while referring to FIG. 21.The cutter according to the third embodiment has the same configurationas the cutter of the first embodiment, except that the laser unit U isreplaced with a laser unit U3. Therefore, only the laser unit U3according to the third embodiment will be explained.

As shown in FIG. 21, a hole 240 d is formed in the left wall of asupport member 240. A knob 242 penetrates through the left wall into arectangular space 240 a of the support member 240. A ring 248 isrotatably engaged with the knob 242 at a right surface of the left wallof the support member 240, so that the knob 242 is axially immovablerelative to the support member 240. Alternatively, the ring 248 can befixed to the right surface of the left wall of the support member 240,and the knob 242 can be loosely supported by the ring 248, so as toprevent the knob 242 from being released from the support member 240.

A screw portion 242A of the knob 242 is screwingly fitted into thefemale screw portion 241 b in the left side of the laser generator 241.A compression spring 243 is supported between the right side wall of thelaser generator 241 and the right side wall of the support member 240.The compression spring 243 urges the laser generator 241 toward the knob242 so that looseness between the laser generator 241 and the knob 242is removed. Because the ring 248 restricts movement of the knob 242, thelaser generator 241 itself slides leftward or rightward in thehorizontal direction when the knob 242 is rotated. Other configurationof the laser unit U3 is same as for the laser unit U described in thefirst embodiment, so further explanation will be omitted. Also, thecutting operations using the cutter of the third embodiment areperformed in the same manner as described for the first embodiment.

Next, the fourth embodiment will be described while referring to FIG.22. The cutter according to the fourth embodiment is the same asdescribed for the first embodiment, except that the laser unit U isreplaced with a laser unit U4. Therefore, only the laser unit U4according to the fourth embodiment will be described hereinafter.

As shown in FIG. 22, a hole 340 d is formed in the left wall of asupport member 340. A knob 342 passes through the hole 340 d into arectangular space 340 a in the support member 340. The knob 342 rotatesidly in the hole 340 d. A pinion 349 is connected to the inward-facingtip of the knob 342, with the pinion 349 positioned in the rectangularspace 340 a in abutment with the inner surface of the left wall of thesupport member 340. The pinion 349 rotates idly with idle rotation ofthe knob 342 in the hole 340 d.

A gear 350 is meshingly engaged with the pinion 349. A horizontallyextending screw shaft 350 a is connected to the center of the gear 350.The screw shaft 350 a is screwingly engaged in a female screw portion341 b in the left side surface of the laser generator 341. A compressionspring 343 is supported between the right wall of the support member 340and the laser generator 341. The compression spring 343 urges the lasergenerator 341 toward the gear 350, thereby eliminating any loosenessbetween the gear 350 and the laser generator 341. When the knob 342 isrotated, the pinion 349 rotates the gear 350. As a result, the lasergenerator 341 slides leftward or rightward horizontally, depending onthe direction of rotation of the knob 342. Other configuration of thelaser unit U4 is the same as for the laser unit U of the firstembodiment, so further explanation will be omitted. Also, the cutteraccording to the fourth embodiment cuts the workpiece M in the samemanner as described for the first embodiment.

Next, the fifth embodiment of the present invention will be describedwhile referring to FIG. 23. The cutter according to the fifth embodimenthas the same configuration as the cutter of the first embodiment, exceptthat the laser unit U is replaced with a laser unit U5. Accordingly,only the laser unit U5 according to the fifth embodiment will bedescribed hereinafter.

A hole 440 d is formed through the left wall of the support member 440,and a knob 442 penetrates through the hole 440 d into the rectangularspace 440 a. A wall 440A is formed inside the support member 440. Apinion 449 is connected to the shaft tip of the knob 442, with the leftwall of the support member 440 sandwiched between the pinion 449 and theknob 442. That is, the pinion 449 is positioned between the left wall ofthe support member 440 and the wall 440A, in abutment with the innersurface of the left wall of the support member 440.

A gear 450 is provided in meshing engagement with the pinion 449. Thegear 450 is disposed between the left wall of the support member 440 andthe wall 440A, in abutment with the inner surface of the left wall ofthe support member 440. A screw shaft 450A is attached to the center ofthe gear 450 and penetrates through the wall 440A into screwingengagement with a female screw portion 441 b formed in the left sidesurface of the laser generator 441. A compression spring 443 issupported between the wall 440A and the left side surface of the lasergenerator 441, for urging the laser generator 441 in a direction awayfrom the knob 442. With this configuration, when the knob 442 isrotated, the pinion 449 rotates the gear 450. The laser generator 441slidingly moves leftward or rightward in the horizontal direction,depending on rotational amount and direction of the knob 442. Further,horizontal movement of the gear 450 is restricted by the wall 440A.Other configuration of the laser unit U5 is the same as for the laserunit U of the first embodiment, so further explanation will be omitted.Also, cutting operations performed by the cutter of the fifth embodimentis in a same manner as for the cutter of the first embodiment.

Next, a cutter according to the sixth embodiment will be described whilereferring to FIG. 24. The cutter according to the sixth embodiment hasthe same configuration as the cutter according to the first embodiment,except that the laser unit U of the first embodiment is replaced with alaser unit U6. Accordingly, only the laser unit U6 of the sixthembodiment will be described hereinafter.

An open portion 540 e is formed in the lower center of the supportmember 540. Right and left hand walls 540A, 540A extend downward fromsupport member 540 on either side of the open portion 540 e. A screw bar551 is fixed between the walls 540A, 540A in a horizontal orientation toextend across the open portion 540 e. A ring screw 552 is screwinglyfitted on the outer periphery of the screw bar 551. The ring screw 552can be moved leftward or rightward between the walls 540A, 540A byrotating the screw ring 552 around the screw bar 551. The outerperipheral edge of the ring screw 552 is fitted in a groove 541 c formedin the lower surface of the laser generator 541. A compression spring543 is supported between right sides of the laser generator 541 and thesupport member 540. The compression spring 543 urges the laser generator541 against the ring screw 552, thereby eliminating any loosenessbetween the groove 541 c of the laser generator 541 and the outerperiphery of the ring screw 552. With this configuration, when the ringscrew 552 is rotated, the laser generator 541 will slidingly moverightward or leftward in a horizontal direction in linking associationwith horizontal movement of the ring screw 552. As a modification, thescrew bar 551 can be screwingly fitted with respect to the wall portions540A, 540A of the support member 540, rather than fixedly fitted on thewall portions. In this case, the ring screw is fixed on the screw bar551. With this modification, by rotating the screw bar 551, the ringscrew is moved leftward and rightward in linking association with themovement of the screw bar 551, so that the laser generator 541 alsoslidingly moves leftward and rightward in the horizontal directiondepending on rotational amount of the screw bar 551.

Next, the seventh embodiment of the present invention will be describedwhile referring to FIGS. 25 to 29. The cutter according to the seventhembodiment has substantially the same configuration as the cutter of thefirst embodiment, except that the laser unit U is replaced with a laserunit U7. Accordingly, the following explanation for the seventhembodiment will be provided for the laser unit U7 only. It should benoted that the laser unit U7 is configured to enable adjustment oforientation of the laser generator 641 in both horizontal and verticaldirections.

As shown in FIG. 25, a hemispherical indentation 40 f is formed in theinner surface of the left sidewall of a support member 640, near thefront of the support member 640. Also, a hemispherical indentation 41 dis formed in a laser generator 641 at a position corresponding to thehemispherical indentation 40 f, that is, in the outer left side surfaceof the laser generator 641, near the front of the laser generator 641. Aball 53 is supported between the hemispherical indentations 40 f, 41 d.The laser generator 641 can be freely pivoted within the rectangularspace 640 a about the ball 53. That is, the ball 53 serves as a pivotfulcrum and the indentations 40 f, 41 d serve as pivot fulcrum bearings.

A first stopper 54 is screwingly fitted in the rear portion of the leftwall of the support member 640. The tip of the first stopper 54 abutsagainst the left surface of the laser generator 641, at a position nearthe rear of the laser generator 641. A compression spring 55 issupported between the right surface of the laser generator 641 and theright wall of the support member 640. The compression spring 55 urgesthe laser generator 641 toward the first stopper 54.

As shown in FIGS. 26 and 27, a second stopper 56 is screwingly fitted inthe lower wall of the support member 640. The second stopper 56 ispositioned near the right side wall of the support member 640 as shownin FIG. 26, that is, opposite from the ball 53 with respect to theleftward and rightward directions, and also in the substantial center ofthe support member 640 with respect to the frontward and rearwarddirections as shown in FIG. 27. The tip of the second stopper 56 abutsagainst the lower surface of the laser generator 641. As shown in FIG.27, two compression springs 57 are disposed between the upper surface ofthe laser generator 641 and the upper wall of the support member 640 onthe opposite side of the laser generator 641 from the second stopper 56.The compression springs 57 urges the laser generator 641 toward thesecond stopper 56. One of the compression springs 57 is disposed to thefront of the second stopper 56 and the other is disposed to the rear ofthe second stopper 56 in order to maintain balance of the lasergenerator 641.

With this configuration, when the first stopper 54 is rotated and movedrightward, the tip of the first stopper 54 presses against the rear edgeportion of the left side surface of the laser generator 641 so that thelaser generator 641 pivots about the ball 53 in the clockwise directionas viewed in FIG. 25. As a result, the laser light L1 will tilt to theleft as viewed in FIG. 25. When the first stopper 54 is rotated once,the laser generator 641 will move by an amount equivalent to themovement amount of the screw portion of the first stopper 54. As aresult, the laser generator 641 can be moved by extremely small amounts.On the other hand, when the first stopper 54 is moved leftward,restorative force of the compression spring 55 will pivot the lasergenerator 641 about the ball 53 in the counterclockwise direction asviewed in FIG. 25. As a result, the laser light L1 will tilt to theright as viewed in FIG. 25. In the example shown in FIG. 25, to alignthe laser light L1 with a horizontal reference line X, the first stopper54 is rotated to move leftward until the laser light L1 is aligned withthe horizontal reference line X. Once alignment has been achieved,rotation of the first stopper 54 is stopped. This enables the positionwhere the laser light L1 falls incident on the workpiece M to beadjusted in the horizontal direction.

When the second stopper 56 is rotated to move upward, then the tip ofthe second stopper presses against the right-hand portion of the lowersurface of the laser generator 641, thereby pivoting the laser generator641 around the ball 53 in the counterclockwise direction as viewed inFIG. 26. As a result, the emitted laser light L1 will rotatecounterclockwise as viewed in FIG. 28 (b). On the other hand, when thesecond stopper 56 is rotated to move downward, then restorative force ofthe compression spring 57 will rotate the laser generator 641 in theclockwise direction as viewed in FIG. 26. As a result, the emitted laserlight L1 will rotate clockwise as viewed in FIG. 28 (b). When the secondstopper 56 is rotated once, the laser generator 641 will move only by anamount equivalent to the axial movement of the stopper 56 caused by thescrewing movement. This enables minute positional adjustment of thelaser generator 641 into alignment with a vertical reference line Y. Inthe example shown in FIGS. 28 (a) and 28 (b), the second stopper 56 isrotated to move downward to align the laser light L1 with the verticalreference line Y. Once the laser light L1 and the reference line Y havebeen aligned in parallel with each other, then rotation of the secondstopper 56 is stopped. In this way, the laser light L1 can be set intoalignment with a vertical reference line Y.

With this configuration, the laser light L1 from the laser generator 641indicates the cutting position on the workpiece M where the cuttingblade 22 will cut the workpiece M when the cutter mechanism 20 is swungdownward. Before cutting the workpiece M, the operator draws a line L2indicating a desired cutting position on the surface of the workpiece Mas shown in FIG. 29. Then, the user aligns the laser light L1 with theline L2. By aligning the laser light L1 with the line L2 in this manner,the cutting blade 22 will also be aligned with the line L2. The userthen energizes the motor 25 to drive rotation of the cutting blade 22.Then, the operator grasps the handle 29 of the cutter mechanism 20 andlowers the cutter mechanism 20 downward, thereby cutting the workpieceM. It is desirable that the position desired to be cut indicated by theline L2 be aligned as accurately as possible with the actual positioncut. Therefore, it is extremely desirable that the position to be cut bythe cutting blade 22 be properly aligned with the laser light L1.

Next, the eighth embodiment of the present invention will be describedwhile referring to FIGS. 30 to 32. The cutter of the eighth embodimenthas substantially the same configuration as the cutter of the seventhembodiment, except that the laser unit U7 is replaced with a laser unitU8 of the eighth embodiment. Accordingly, only the laser unit U8 of theeighth embodiment will be described in the following text.

As shown in FIGS. 30 and 31, an arc-shaped indentation 40 g is formed inthe front edge at the inner surface of the left wall of the supportmember 740. An arc-shaped protruding portion 41 e, which corresponds tothe shape of the arc-shaped indentation 40 g, is formed near the frontof the left surface of the laser generator 741. With this configuration,the laser generator 741 can be freely pivoted around the arc-shapedprotruding portion 41 e within the space 740 a. A first stopper 754 isscrewingly engaged in the left sidewall of the support member 740 at aposition to the rear of the arc-shaped indentation 40 g. The tip of thefirst stopper 754 abuts against a rearward position on the left side ofthe laser generator 741. A compression spring 755 for urging the lasergenerator 741 towards the first stopper 754 is supported between theright surface of the laser generator 741 and the support member 740.

As shown in FIGS. 31 and 32, a second stopper 756 is screwingly fittedin the lower side of the support member 740, with the tip of the secondstopper 756 in abutment against the lower surface of the laser generator741. As shown in FIG. 31, the second stopper 756 is located on theopposite side of the light emitting portion 41 a than the arc-shapedindentation 40 g and the arc-shaped protruding portion 41 e in theleftward and rightward directions. That is, the second stopper 756 ispositioned to the right side of the light emitting portion 41 a. Asshown in FIG. 32, the second stopper 756 is positioned substantially inthe center of the support member 740 in the front and rear directions.Compression springs 757, 757 for urging the laser generator 741 againstthe second stopper 756 are supported between the upper surface of thelaser generator 741 and the support member 740. The compression springs757, 757 are disposed on the opposite side of the laser generator 741than the second stopper 756. One of the compression springs 757 isdisposed to the front of the second stopper 756 and one to the rear ofthe second stopper 756 in order to properly balance the laser generator741.

With this configuration, the user rotates the first stopper 754 to movethe first stopper 754 leftward or rightward in order to align the laserlight L1 with the horizontal reference line X shown in FIG. 30.Accordingly, the laser generator 741 pivots clockwise orcounterclockwise as viewed in FIG. 30 around the arc-shaped protrudingportion 41 e. The user stops rotating the first stopper 754 once thelaser light L1 is aligned with the horizontal reference line X.

In order to align the laser light L1 emitted from the laser generator741 as shown in FIG. 28 (a) into alignment with the vertical referenceline Y shown in FIG. 28 (b), the operator rotates the second stopper 756to move the second stopper 756 upward or downward. This will pivot thelaser generator 741 in the corresponding clockwise or counterclockwisedirections as viewed in FIG. 31 around the arc-shaped protruding portion41 e. The user stops rotating the second stopper 756 once the laserlight L1 is aligned with the vertical reference line Y. Operation forcutting the workpiece M using the cutter of the eighth embodiment arethe same as described for the seventh embodiment, so will be omittedhere.

Next, a cutter according to the ninth embodiment of the presentinvention will be described while referring to FIGS. 33 to 35. Thecutter according to the ninth embodiment has substantially the sameconfiguration as the cutter according to the seventh embodiment, exceptthat the laser unit U7 is replaced with a laser unit U9. Therefore, thefollowing explanation will be provided for the laser unit U9 only.

As shown in FIGS. 33 to 35, an angular indentation 40 h is formed in theinner surface of the left wall of the support member 840, near the frontof the support member 840. An angular protrusion 41 f is formed at theleft side of the laser generator 841, at a position corresponding to theposition of the angular indentation 40 h. Other configuration is thesame as described for the eighth embodiment.

With the configurations of the eighth and ninth embodiments, theposition where the laser light L1 falls incident on the workpiece M canbe adjusted in precise alignment with vertical and horizontal referencelines X, Y in a manner similar to that described in the seventhembodiment, so that the laser light L1 can be properly and easilypositioned into alignment with a desired cutting position.

Next, the tenth embodiment of the present invention will be describedwhile referring FIGS. 36 to 39. The cutter according to the tenthembodiment has substantially the same configuration as the cutterdescribed in the first embodiment, except that the laser unit U isreplaced with a laser unit U10. The laser unit U10 is capable ofadjusting the width W1 of the laser light L1. Therefore, the followingexplanation of the tenth embodiment will be provided only for the laserunit U10 and explanation of other configuration will be omitted.

As shown in FIGS. 36 and 37, the laser unit U10 is provided with a lasercase 41A, a laser light source 58, a convex lens 59, a lever 59A, and acylindrical lens 60. A female screw portion 41 g is formed along theinterior surface of the laser case 41A. The convex lens 59 is held by anannular lens holder 59B, whose outer peripheral surface is formed with amale screw which is threadingly engaged with female screw portion 41 g.Thus, the cylindrical lens 60 is rotatable within the laser case 41A asguided by the female screw portion 41 g. The laser light source 58 isdisposed to the rear of the convex lens 59. The convex lens 59 regulatesthe focal point of the laser light L1.

A cutout portion 41 j is formed in the front surface of the laser case41A. The cylindrical lens 60 is disposed in the cutout portion 41 j at aposition in front of the convex lens 59. The cylindrical lens 60 ispartially exposed from the front surface of the laser case 41A throughthe cutout portion 41 j. The cylindrical lens 60 refracts the laserlight L1 passing through the convex lens 59 into parallel rays.

An elongated hole 41 h is formed on the upper surface of the laser case41A. The lever 59A is attached on the outer peripheral surface of theconvex lens 59 and protrudes outward from the laser case 41A through theelongated hole 41 h. The operator rotates the lever 59A to move theconvex lens 59 either forward or rearward. A scale plate 41D thatindicates various optional widths W1 for the laser light L1 is providedadjacent to the elongated hole 41 h on the upper surface of the lasercase 41A. The operator can determine the width W1 of the laser light L1by reading the scale marked on the scale plate 41D.

When the convex lens 59 moves in association with the pivoting movementof the lever 59A, the width W1 of the laser light L1 will change asshown in FIG. 38. That is to say, when the convex lens 59 moves rearwardas indicated by arrow F in FIG. 37, then the width W1 of the laser lightL1 will decrease. On the other hand, when the convex lens 59 movesforward as indicated by arrow G in FIG. 37, the width W1 will increase.According to the present embodiment, when the convex lens 59 is locatedat the position I as indicated in dotted line in FIG. 38, the laserlight L1 will be emitted with a minimum width Wmin of 0.5 mm. On theother hand, when the convex lens 59 is located at position J indicatedby solid line in FIG. 38, the laser light L1 will have a maximum widthWmax of 3.0 mm.

Next, an explanation will be provided for operations for using theabove-described configuration to cut the workpiece M as shown in FIG.39. Before starting operations to cut the workpiece M, the operatordraws the line L3 on the workpiece M to indicate a desired length □l ofthe workpiece M to be used. When the cutting blade 22 has a width W2 of0.5 mm (Wmin) then, the operator aligns the lever 59A to the mark on thescale plate 41D indicating 0.5 mm. As a result, the convex lens 59 willmove to the position I so that the width W1 of the laser light L1 is setto 0.5 mm, which is the minimum possible width of the laser light L1 inthis example. Next, the user moves the workpiece M until the laser lightL1 and the line L3 are in alignment with each other. Next, after turningon the motor of the cutter, the user grasps the handle 29 and pivots thecutter mechanism 20 downward to cut the workpiece M with the cuttingblade 22.

When the cutting blade 22 has a width W2 of, for example, 3.0 mm, whichis the maximum width of the laser light L1, then the operator aligns thelever 59A with the mark indicating 3.0 mm on the scale plate 41D. As aresult, the convex lens 59 will move to the position J so that the widthW1 of the laser light L1 is set to 3.0 mm, which is the maximum possiblewidth that the laser unit U10 can emit the laser light L1. Next, theoperator moves the workpiece M until the laser light L1 and the line L3are aligned with each other. Then the user cuts the workpiece M asdescribed above.

Next, the eleventh embodiment of the present invention will be describedwhile referring to FIGS. 40 and 41. The cutter according to the eleventhembodiment has the same configuration as the cutter described in thefirst embodiment, except that the laser unit U is replaced with a laserunit U11. Therefore, the following explanation will be provided for thelaser unit U11 only.

As shown in FIGS. 40 and 41, the laser unit U11 includes a laser case141A, a movement member 61, and a cylindrical lens 60. Also, althoughnot shown in the drawings, a laser light source is provided in the lasercase 141A. The cylindrical lens 60 is provided in front of the laserlight source for refracting the laser light L1 into parallel rays. Thecylindrical lens 60 protrudes from the front surface of the laser case141A. A groove 41 i is formed in the front part of the upper surface ofthe laser case 141A. The movement member 61 is mounted in the groove 41i at a position in front of the cylindrical lens 60. The movement member61 is freely movable leftward and rightward horizontally as guided bythe groove 41 i. A protrusion portion 41C is formed in the front of thelaser case 141A. A screw member 62 is screwingly fitted in theprotrusion portion 41C and the movement member 61, with the base of thescrew member 62 in abutment with the outer side of the protrusionportion 41C and the tip of the screw member 62 screwingly engaged in theinner surface of the movement member 61. A slit H is defined between theprotrusion portion 41C and the movement member 61. With thisconfiguration, when the screw member 62 is rotated, the movement member61 moves leftward or rightward according to the rotation direction ofthe screw member 62, so that the width W3 of the slit H can be adjusted.A scale plate 41D including a marked scale is disposed at the frontupper side of the laser case 141A, adjacent to the protrusion portion41C and the movement member 61.

The laser light L1 that passes through the cylindrical lens 60 isemitted only through the slit H between the movement member 61 and theprotrusion portion 41C. The laser light L1 other than that emitted fromthe slit H is blocked by the movement member 61 and the protrusionportion 41C. That is to say, when the movement member 61 is moved usingthe screw member 62, the width W3 of the slit H changes, so that thewidth W1 of the laser light L1 emitted through the slit H can bechanged. When the movement member 61 moves leftward as viewed in FIG.40, then the width W1 of the laser light L1 decreases as shown in FIG.40. On the other hand, when the movement member 61 is moved to the rightas viewed in FIG. 41, then the width W1 of the laser light L1 increasesas shown in FIG. 41. By moving the movement member 61 while referring tothe gauge marks on the scale plate 41D, the user can adjust the width W1of the laser light L1. According to the present embodiment, the width W1of the laser light L1 can be adjusted between 0.5 mm and 3.0 mm.

According to the eleventh embodiment, portions of the laser light L1 areblocked by the movement member 61 and the protrusion portion 41C so thatcompared to the configuration of the tenth embodiment, the contour ofthe laser light L1 is sharper. By matching the width W1 of the laserlight L1 with width W2 of the cutting blade 22, alignment of the cuttingposition can be easily and accurately performed.

FIG. 42 shows a cutter D2 according to the twelfth embodiment. In thisembodiment, a laser unit U12 is fixed to the lower rear portion of thecover 23 of the cutter mechanism 20. As the laser unit, any of the laserunits described in the first through eleventh embodiments is available.

FIGS. 43 through 46 show a cutter D3 according to the thirteenthembodiment, wherein like parts and components are designated by the samereference numerals as those shown in the first embodiment shown in FIG.8. In the thirteenth embodiment, a holder 110 has an upper portionprovided with a shaft support portion 110A where a pair of slide shafts81A, 81B are movably supported. More specifically, the shaft supportportion 110A is formed with a first hole 111 having a diameter greaterthan an outer diameter of the slide shaft 81A and a second hole 112having a diameter equal to an outer diameter of the slide shaft 81B. Apair of bolts 113, 114 vertically extend through and are threadinglyengaged with the shaft support portion 110A at a diametrically oppositeposition of the first hole 111. Each inner side of the bolt 113,114, aplastic support 115 is provided slidably in the radial direction of thefirst hole 111. Each plastic support 115 has an inner end configured tomatch the outer peripheral surface of the slide shaft 81A.

The slide shaft 81B is axially slidably movable with respect to thesecond hole 112, and the slide shaft 81A is axially slidably movablewith respect to the plastic supports 115. Further, the slide shaft 81Ais rotatable about its axis upon loosening the bolt 113, and angularrotational position of the slide shaft 81A can be fixed upon fasteningthe bolt 114. In the latter case, the slide shaft 81A is still axiallyslidably movable with respect to the plastic supports 115.

A stop member 83 is fixed to each rear end of the slide shaft 81A, 81Bso as to regulate the frontmost position of the slide shafts 81A, 81B.On the other hand, a front end of the slide shaft 81A is connected to ahinge holder 82. Each of the slide shafts 81A, 81B is covered with abellows (not shown) along its entire length except the shaft supportportion 110A.

The hinge holder 82 has an upper portion pivotally supports the cuttermechanism 20 through the shaft 11. Thus, the cutter mechanism 20 ismechanically linked with the slide shafts 81A, 81B through the hingeholder 82. Consequently, the cutter mechanism 20 can be slanted inaccordance with the angular rotation of the slide shaft 81A. Further,the cutter mechanism 20 can be moved frontwardly or rearwardly inaccordance with the axial sliding movement of the slide shafts 81A, 81B.Incidentally, a cutter having such slide shafts for moving the cuttermechanism in the horizontal direction is described in U.S. Pat. No.5,060,548.

A laser unit U13 is fixed to the hinge holder 82. That is, a supportmember 40 of the laser unit U13 is fixed to the lower portion of thehinge holder 82, and a laser generator 41 of the laser unit U13 ishoused in the support member 40. As the laser unit U13, any one of thelaser units of the first through eleventh embodiment is available.

A dust cover 84 made from a rubber is fixed to the rear side of the sawcover 23 for preventing cutting chips from being adhered to the frontface of the laser generator 41. To this effect, the dust cover 84 can bebrought into alignment with and in front of the laser generator 41 whenlowering cutter mechanism 20.

Inclination of the cutting mechanism 20 (see arrow A in FIG. 44) ismainly controlled by controlling pivoting amount of the holder 110 aboutthe shaft 4 relative to the base 1. The pivot angle can be fixed by theclamp lever 5 as described above. Further, a minute inclination of thecutting mechanism 20 can be controlled by rotating the slide shaft 81Aabout its axis upon loosening and then tightening the bolts 113, 114. Inthis case, because the hinge holder 82 is also moved concurrently withthe inclining movement of the cutter mechanism 20, the positionalrelationship between the circular saw blade 22 and the laser generator41 can be maintained unchanged. Consequently, the laser light cancorrectly indicate the position of the circular saw blade 22.

Further, because the laser generator 41 is positioned at the front sideof the slide shaft 81, laser light can be irradiated brightly eventoward a workpiece M having a relatively large width ml (FIG. 43). If aworkpiece M has a relatively large width which is not subjected tocutting only by the vertical pivotal movement of the circular saw blade22, the slide shafts 81A, 81B are moved frontwardly for complete cuttingover the width m1. In this case, because the laser generator 41 is alsomoved frontwardly, the laser light can irradiate brightly to theworkpiece so as to facilitate alignment of the laser light with thecutting mark line.

Furthermore, as shown in FIG. 46, the cutting chips are directedrearwardly as shown by an arrow B during cutting operation by thecircular saw blade 22. However, the cutting chips are trapped by thedust cover 84. Therefore, the dust cover 84 can prevent the cuttingchips from being adhered onto the light emitting side of the lasergenerator 41.

While the invention has been described in detail and with reference tospecific embodiments thereof, it would be apparent to those skilled inthe art that various changes and modifications may be made thereinwithout departing from the sprit and scope of the invention. Forexample, although the above described embodiments pertain to a tabletopcutter with a swingable blade casing that supports a circular blade, thepresent invention can be applied to other types of cutters, such as bandsaws for example.

In addition, the configuration described in either the tenth or eleventhembodiments can be easily combined with any of the alignment-adjustingconfigurations described in the second to ninth embodiments.

Also, the cleaning mechanism described with reference to FIGS. 15 to 18can be used with any of the cutters described in the second tothirteenth embodiments.

1. A miter saw comprising: a base portion for supporting a workpiece; acutter portion pivotable between a raised non-cutting position and alower cutting position and adapted to rotatably support a circular sawblade; a laser generator for projecting laser light focused into a linewhich is narrow relative to the width of a blade edge of the circularsaw blade, substantially all of said laser light being projected belowthe circular saw blade when the cutter portion is in the raisedposition; and wherein the laser generator is operable to project thenarrow focused line of laser light onto the workpiece at any location onthe workpiece adjacent to or directly beneath the position of thecircular saw blade.
 2. A miter saw comprising: a base portion forsupporting a workpiece; a sliding mechanism supported on the baseportion; a cutter portion pivotally mounted on said sliding mechanismwhereby the cutter portion is movable relative to the base portion onsaid sliding mechanism, said cutter portion being pivotable between araised non-cutting position and a lower cutting position and adapted torotatably support a circular saw blade; a laser generator for projectinglaser light focused into a line which is narrow relative to the width ofa blade edge of the circular saw blade from a portion of the slidingmechanism proximate to said cutter portion, whereby substantially all ofsaid laser light is projected below the circular saw blade when thecutter portion is in the raised position; and wherein the lasergenerator is operable to project the narrow focused line of laser lightonto the workpiece at any location on the workpiece adjacent to ordirectly beneath the position of the circular saw blade.